From d6f4eb55f93ca687b47331db84961949b83e08be Mon Sep 17 00:00:00 2001
From: Luke Dashjr <luke-jr+git@utopios.org>
Date: Mon, 15 Feb 2016 08:49:26 +0000
Subject: [PATCH] Qt/Options: Configure maxmempool using rwconf

---
 src/qt/optionsdialog.cpp | 10 +++++++++-
 src/qt/optionsdialog.h   |  1 +
 src/qt/optionsmodel.cpp  | 22 ++++++++++++++++++++++
 src/qt/optionsmodel.h    |  1 +
 4 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/src/qt/optionsdialog.cpp b/src/qt/optionsdialog.cpp
index 297b3fab1c..2bf01db8c6 100644
--- a/src/qt/optionsdialog.cpp
+++ b/src/qt/optionsdialog.cpp
@@ -13,6 +13,7 @@
 #include <qt/guiutil.h>
 #include <qt/optionsmodel.h>
 
+#include <common/args.h>
 #include <common/system.h>
 #include <index/blockfilterindex.h>
 #include <interfaces/node.h>
@@ -20,8 +21,8 @@
 #include <netbase.h>
 #include <outputtype.h>
 #include <txdb.h>
+#include <txmempool.h> // for maxmempoolMinimum
 #include <util/strencodings.h>
-
 #include <chrono>
 
 #include <QApplication>
@@ -207,6 +208,12 @@ OptionsDialog::OptionsDialog(QWidget* parent, bool enableWallet)
     maxorphantx->setMaximum(std::numeric_limits<int>::max());
     CreateOptionUI(verticalLayout_Mempool, maxorphantx, tr("Keep at most %s unconnected transactions in memory"));
 
+    maxmempool = new QSpinBox(tabMempool);
+    const int64_t nMempoolSizeMinMB = maxmempoolMinimumBytes(gArgs.GetIntArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT_KVB) * 1'000) / 1'000'000;
+    maxmempool->setMinimum(nMempoolSizeMinMB);
+    maxmempool->setMaximum(std::numeric_limits<int>::max());
+    CreateOptionUI(verticalLayout_Mempool, maxmempool, tr("Keep the transaction memory pool below %s MB"));
+
     QGroupBox * const groupBox_Spamfiltering = new QGroupBox(tabMempool);
     groupBox_Spamfiltering->setTitle(tr("Spam filtering"));
     QVBoxLayout * const verticalLayout_Spamfiltering = new QVBoxLayout(groupBox_Spamfiltering);
@@ -460,6 +467,7 @@ void OptionsDialog::setMapper()
     mempoolreplacement->setCurrentIndex(current_mempoolreplacement_index);
 
     mapper->addMapping(maxorphantx, OptionsModel::maxorphantx);
+    mapper->addMapping(maxmempool, OptionsModel::maxmempool);
 
     /* Window */
 #ifndef Q_OS_MACOS
diff --git a/src/qt/optionsdialog.h b/src/qt/optionsdialog.h
index aaa8f9a316..13cad80357 100644
--- a/src/qt/optionsdialog.h
+++ b/src/qt/optionsdialog.h
@@ -90,6 +90,7 @@ private:
 
     QValueComboBox *mempoolreplacement;
     QSpinBox *maxorphantx;
+    QSpinBox *maxmempool;
 };
 
 #endif // BITCOIN_QT_OPTIONSDIALOG_H
diff --git a/src/qt/optionsmodel.cpp b/src/qt/optionsmodel.cpp
index 926a95c48e..fd4ef110fe 100644
--- a/src/qt/optionsmodel.cpp
+++ b/src/qt/optionsmodel.cpp
@@ -14,6 +14,7 @@
 #include <common/args.h>
 #include <index/blockfilterindex.h>
 #include <interfaces/node.h>
+#include <kernel/mempool_options.h> // for DEFAULT_MAX_MEMPOOL_SIZE_MB
 #include <mapport.h>
 #include <net.h>
 #include <net_processing.h>
@@ -637,6 +638,8 @@ QVariant OptionsModel::getOption(OptionID option, const std::string& suffix) con
         return CanonicalMempoolReplacement(*this);
     case maxorphantx:
         return qlonglong(gArgs.GetIntArg("-maxorphantx", DEFAULT_MAX_ORPHAN_TRANSACTIONS));
+    case maxmempool:
+        return qlonglong(node().mempool().m_opts.max_size_bytes / 1'000'000);
     default:
         return QVariant();
     }
@@ -970,6 +973,25 @@ bool OptionsModel::setOption(OptionID option, const QVariant& value, const std::
         }
         break;
     }
+    case maxmempool:
+    {
+        if (changed()) {
+            long long nOldValue = node().mempool().m_opts.max_size_bytes;
+            long long nNv = value.toLongLong();
+            std::string strNv = value.toString().toStdString();
+            node().mempool().m_opts.max_size_bytes = nNv * 1'000'000;
+            gArgs.ForceSetArg("-maxmempool", strNv);
+            gArgs.ModifyRWConfigFile("maxmempool", strNv);
+            if (nNv < nOldValue) {
+                LOCK(cs_main);
+                auto node_ctx = node().context();
+                assert(node_ctx && node_ctx->mempool && node_ctx->chainman);
+                auto& active_chainstate = node_ctx->chainman->ActiveChainstate();
+                LimitMempoolSize(*node_ctx->mempool, active_chainstate.CoinsTip());
+            }
+        }
+        break;
+    }
     default:
         break;
     }
diff --git a/src/qt/optionsmodel.h b/src/qt/optionsmodel.h
index 38a984331a..a5a32ff662 100644
--- a/src/qt/optionsmodel.h
+++ b/src/qt/optionsmodel.h
@@ -82,6 +82,7 @@ public:
         peerblockfilters,       // bool
         mempoolreplacement,
         maxorphantx,
+        maxmempool,
         OptionIDRowCount,
     };